This invention relates to a semiconductor laser apparatus usable as a light source of an optical information processing apparatus or an optical communications apparatus.
The semiconductor laser apparatus has recently been used widely as the light source for an optical information processing apparatus such as compact disc devices and video disc or optical communications apparatus.
Such semiconductor laser apparatus cannot be easily reduced in cost, as compared with LED or other semiconductor devices.
The difficulty of reducing the cost of semiconductor laser apparatus, as compared with LED and other semiconductor devices, is due to not only the problem of yield, but also the expensive materials and components.
The conventional semiconductor laser apparatus is of the can type as shown in FIG. 11, in which a silicon submount 32 and a laser chip 33 are disposed on a gold-plated stem 31 of about 1 .mu.m in thickness, and its surface is further covered with a cap 35 having a window glass 34 coated with an anti-reflection (AR) film. This cap 35 is filled with N.sub.2 gas.
In such conventional semiconductor laser apparatus, since parts other than the laser chip 33, such as stem 31 and cap 35, are expensive, cost reduction is limited, and further, structurally, since the semiconductor laser apparatus has a wide-spread radiated beam, a lens system for correcting the beam is necessary, and the entire optical pickup device for composing the optical system becomes expensive.